Partial imprint of the Yucatan crater created by the asteroid responsible for the Cretaceous-Tertiary Extinction Event.

Walter Alvarez teaches geology at Berkley and his main contribution to the history of science is the theory that the dinosaur era was brought to an end by a giant asteroid that landed on Yucatan peninsula 60 million years ago. The footprint of the asteroid is truly immense, more 180 km (110 miles) wide.

At the Microsoft Faculty Summit which I attended, he presented his take on teaching and studying what he calls “Big History“, a heuristic and educational perspective proposed by David Christian, an Anglo-Australian scholar . Big History tries to help us comprehend the fact that natural history is a million longer than human history and that we tend to over emphasize our own human-based chronological perspective when judging historical periods. History should be divided into four stages, says Alvarez, each an order of magnitude larger than the next. Current events = 5 years, Human history = 5000 years, Human prehistory = 5 million years, Natural history = 5 billion years. One way to get around this exponential jumps trough time is to plot events on a log scale. This procedure does not, however, help human minds understand time scales properly.

Walter Alvarez’s student Roland Saekow used Seadragon, a vizualization tool powered by Microsoft Silverlight, which allows zooming in and out of timelines in a way that gives a sense for how large the time jumps are. The advantage of this tool is that you see the giant leaps of scale between the different levels of Big History.